1. Field of the Invention
The invention relates to a back contact solar module and an electrode soldering method therefor, and especially relates to a back contact solar module with a curved solder part and an electrode soldering method therefor.
2. Description of the Prior Art
As the solar photovoltaic conversion efficiency is getting improving, solar cells have been one of the choices of power sources for electronic apparatuses. A current solar module generally includes a plurality of solar cells formed on a substrate. These solar cells need to be electrically connected in series so as to provide needed voltage and current. A common back contact solar module is illustrated herein as an example. It uses a straight metal ribbon to dispose between adjacent solar cells to be soldered onto the electrode solder pads of the adjacent solar cells. Because the temperature of a common soldering in series may reach more than two hundreds degrees, there is residual stress induced inside the metal ribbon when the temperature is back to a room temperature after the metal ribbon is soldered onto the electrode solder pads. If the residual stress is too high or the distribution thereof is excessively non-uniform, the soldering may fail or the solar cells may break. Furthermore, the solar cells after being soldered in series are to be packed under a lamination process for structural protection. At this moment, the metal ribbon suffers pressure leading to inducing internal stress. The internal stress interacts with the above residual stress may also make the soldering fail or the solar cells break.